Fluid circulation system for dishwasher appliances

Abstract

Fluid circulation systems for dishwasher appliances are provided. A dishwasher appliance includes a tub that defines a wash chamber. A fluid circulation system includes a sump for receiving fluid from the wash chamber, the sump comprising a chamber having a sidewall and a base wall. The fluid circulation system further includes a pump, the pump including an impeller disposed within the chamber. The fluid circulation system further includes a filter disposed within the chamber and surrounding the impeller, the filter including a sidewall, the sidewall defining a plurality of perforations extending therethrough. In some embodiments, a volume within the filter is greater than a volume between the sidewall of the chamber and the sidewall of the filter for a given height from the base wall. In some embodiments, volumes of the plurality of perforations increase along a height from the base wall.

What is claimed is: 
     
       1. A fluid circulation system for a dishwasher appliance, the dishwasher appliance defining a vertical direction, a lateral direction, and a transverse direction which are mutually orthogonal, the dishwasher appliance comprising a tub that defines a wash chamber, the fluid circulation system comprising:
 a sump positioned below the wash chamber along the vertical direction for receiving fluid from the wash chamber, the sump comprising a chamber having a sidewall and a base wall; 
 a pump, the pump comprising an impeller disposed within the chamber; and 
 a filter disposed within the chamber and surrounding the impeller, the filter comprising a sidewall extending along the vertical direction between the base wall of the chamber and a top wall of the filter, the sidewall of the filter spaced from the sidewall of the chamber and radially aligned with the impeller, the sidewall of the filter defining a plurality of perforations extending therethrough, individual volumes of each of the plurality of perforations increasing along the vertical direction from the base wall of the chamber; 
 wherein a volume within the filter is greater than a volume between the sidewall of the chamber and the sidewall of the filter at any given height from the base wall. 
 
     
     
       2. The fluid circulation system of  claim 1 , wherein the increase is continuous. 
     
     
       3. The fluid circulation system of  claim 1 , wherein the increase is step-wise. 
     
     
       4. The fluid circulation system of  claim 1 , wherein the sidewall of the chamber extends from the base wall along the vertical direction. 
     
     
       5. The fluid circulation system of  claim 1 , wherein at least a portion of an inner surface of the sidewall of the chamber extends from the base wall at an angle to the vertical direction. 
     
     
       6. The fluid circulation system of  claim 5 , wherein the portion of the inner surface extends from the base wall inward towards filter. 
     
     
       7. The fluid circulation system of  claim 1 , wherein the sump further comprises an upper receptacle for receiving the fluid and flowing the fluid to the chamber. 
     
     
       8. The fluid circulation system of  claim 1 , further comprising an outlet conduit in fluid communication with a diffuser of the pump. 
     
     
       9. The fluid circulation system of  claim 1 , wherein the pump further comprises a motor disposed external to the sump and a shaft extending through the base wall of the chamber, the shaft connecting the motor and the impeller. 
     
     
       10. A fluid circulation system for a dishwasher appliance, the dishwasher appliance defining a vertical direction and comprising a tub that defines a wash chamber, the fluid circulation system comprising:
 a sump positioned below the wash chamber along the vertical direction for receiving fluid from the wash chamber, the sump comprising a chamber having a sidewall and a base wall; 
 a pump, the pump comprising an impeller disposed within the chamber; and 
 a filter disposed within the chamber and surrounding the impeller, the filter comprising a sidewall extending along the vertical direction between the base wall of the chamber and a top wall of the filter, the sidewall of the filter spaced from the sidewall of the chamber and radially aligned with the impeller, the sidewall of the filter defining a plurality of perforations extending therethrough, wherein individual volumes of each of the plurality of perforations increase along the vertical direction from the base wall. 
 
     
     
       11. The fluid circulation system of  claim 10 , wherein the increase is continuous. 
     
     
       12. The fluid circulation system of  claim 10 , wherein the increase is step-wise. 
     
     
       13. The fluid circulation system of  claim 10 , wherein the dishwasher appliance defines a vertical direction, and wherein the sidewall of the chamber extends from the base wall along the vertical direction. 
     
     
       14. The fluid circulation system of  claim 10 , wherein the dishwasher appliance defines a vertical direction, and wherein at least a portion of an inner surface of the sidewall of the chamber extends from the base wall at an angle to the vertical direction. 
     
     
       15. The fluid circulation system of  claim 14 , wherein the portion of the inner surface extends from the base wall inward towards filter. 
     
     
       16. The fluid circulation system of  claim 10 , wherein the sump further comprises an upper receptacle for receiving the fluid and flowing the fluid to the chamber. 
     
     
       17. The fluid circulation system of  claim 10 , further comprising an outlet conduit in fluid communication with a diffuser of the pump. 
     
     
       18. The fluid circulation system of  claim 10 , wherein the pump further comprises a motor disposed external to the sump and a shaft extending through the base wall of the chamber, the shaft connecting the motor and the impeller.